|DEVNAME(3)||FreeBSD Library Functions Manual||DEVNAME(3)|
NAMEdevname — get device name
LIBRARYStandard C Library (libc, -lc)
SYNOPSIS#include < sys/stat.h>
#include < stdlib.h>
devname( dev_t dev, mode_t type);
devname_r( dev_t dev, mode_t type, char *buf, int len);
fdevname( int fd);
fdevname_r( int fd, char *buf, int len);
DESCRIPTIONThe devname() function returns a pointer to the name of the block or character device in /dev with a device number of dev, and a file type matching the one encoded in type which must be one of S_IFBLK or S_IFCHR. To find the right name, devname() asks the kernel via the kern.devname sysctl. If it is unable to come up with a suitable name, it will format the information encapsulated in dev and type in a human-readable format.
The fdevname() and fdevname_r() function obtains the device name directly from a file descriptor pointing to a character device. If it is unable to come up with a suitable name, these functions will return a NULL pointer.
devname() and fdevname() return the name stored in a static buffer which will be overwritten on subsequent calls. devname_r() and fdevname_r() take a buffer and length as argument to avoid this problem.
int fd; struct stat buf; char *name; fd = open("/dev/tun"); fstat(fd, &buf); printf("devname is /dev/%s\n", devname(buf.st_rdev, S_IFCHR)); printf("fdevname is /dev/%s\n", fdevname(fd));
HISTORYThe devname() function appeared in 4.4BSD. The fdevname() function appeared in FreeBSD 8.0.
|February 22, 2005||FreeBSD|